Hi Moses, I've got a bit of news for you.
Before I went off and bought a new PDM from Mopar Parts (I had much trouble finding an Australian dealer that sold RHD versions, and was only ever directed to US sites which sold them for $175 Aus dollars).
So...
I went down to my local auto scrap yard, and sought out the single 1998 Jeep Cherokee XJ that they had there.
I went to the passenger door and removed the PDM as per your instructions (went off without a hitch!).
I then went home and popped my Jeeps door panel off, swapped PDMs, put it all back, AND....
Nothing.
The interesting thing though, is that the door lock still worked with the Original PDM, and the one I pulled from the Auto yard.
(As I said, the power locks still worked in the passenger door, just not the power windows...)
Does this suggest that there is an underlying issue with the power window wiring, deep within the door itself?
Just to re-iterate, none of the power windows are able to be used from their respective doors, except from the Drivers door panel.
Regards,
AusJeep.